Adjustable form lock

ABSTRACT

A form for casting structural concrete members has a bottom with at least one side wall resiliently hinged thereto for movement between an open-form position that provides stripping draft and a closed-form position defining a corresponding portion of a member to be cast. Means are provided for pivoting the side wall about the bottom and locking the side wall in a closed-form position. Adjusting means acting upon the side wall pivoting the locking means enable the position of the side wall to be adjusted when locked in the closed-form position.

[m 3,765,641 [451 Oct. 16,1973

[ ADJUSTABLE FORM LOCK [76] Inventor:

Primary Examiner-J. Spencer Overholser Assistant Examiner-John S. Brown Attorney-F. W. Anderson et a].

e k a a MP 8 i m v t-m e mk 3 L w v A m e 8! LB 22 Filed: Sept. 29, 1971 App]. No.: 184,733

[57] ABSTRACT A form for casting structural concrete members has a bottom with at least one side wall resiliently hinged thereto for movement between an open-form position [58] Field of Search.................... 249/161, 163, 165,

249/166 219 that provides stripping draft and a closed-form position defining a corresponding portion of a member to be cast. Means are provided for pivoting the side wall about the bottom and locking the side wall in a closed- [56] References Cited 249/ 161 X 7 Claims, 3 Drawing Figures S m m E Tm Am P m" S m E l Tm m ARC T SDM m 31 H%% NHH U H 64 87 .1. 2 0 91 33 1,866,599 7/1932 Pettis.. 2,217,140 10/1940 PATENIEDHEI 1 91 3.765.641

' sum 1 or 2 FIG E III'III" INVENTOR. LAWRENCE F. TU MEY ATTORNEYS.

PATENIEDnm 16 1915 saw 210 2 ADJUSTABLE FORM LOCK BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to forms for casting structural concrete members and more particularly to such forms having a hinged side wall with pivoting and locking means to position the side wall in a particular closedform position.

2. Description of the Prior Art US. Pat. No. 3,071,834 shows a form with a hinged side wall that can be pivoted between an open-form stripping position and a closed-form casting position. Means are provided for adjusting the closed-form casting position of the side wall, but such adjustment must be made on a trial and error basis when the side wall is in an open-form position because resilient force actingupon the hinged side wall when locked in a closedform position tends to move the adjusting means unless the adjusting means are secured in place to preclude adjustment.

US. Pat. No. 1,705,201 shows a mold for concrete slabs having a resilient side wall and a rotatable cam for flexing the side wall inwardly to a closed-mold position. Rotation of the cam in one direction locks the mold in the closed-mold position and rotation in the opposite direction releases the side wall and permits it to flex outwardly to provide stripping draft for removing the molded product. No means are shown for adjusting the closed-form position of the side wall.

US. Pat. No. 555,345 shows a mold wall that can be locked in place by a cam which is adjustable laterally of the mold wall to provide for casting products of various size. Such adjustment, however, cannot be made when the cam is locking the mold wall in a closed-mold position.

Form locks should be adjustable to align a movable side wall of the form in a true casting position when the form is locked. It is desirable to make such adjustment at the time the form is fabricated and final adjustment thereof should be made after field installation. Known adjustable form locks do not permit adjustment of the lock when the movable side wall is in a closed-form position. This presents a problem in making adjustment because such adjustment must be made with the side wall in an open-form position and then checked in a closed-form position. Consequently, a lengthy trial and error process is often necessary.

SUMMARY OF THE INVENTION A hinged side wall of a concrete form can be pivoted from an open-form stripping position to a closed-form casting position, locked in the casting position, and then adjusted for proper alignment while locked. This feature provides for a more accurate adjustment of the side wall in a minimum amount of adjusting time. Details of the form and lock provide for a compact structure with minimum shipping volume and floor space requirements, protection of the lock from concrete spillage, and a more reliable lock that can withstand vibration without coming loose.

Adjusting means acting upon the form side wall pivoting and locking means and against the resilient hinge strength of the side wall provides for alignment of the side wall in a true vertical closed-form position when the side wall is locked. The adjusting means preferably includes a set screw threadably' adjustable through a sleeve to bear against a deflectable cantilever reaction member of the side wall pivoting and locking means. The end of the set screw that faces outwardly from the side wall is adapted to be rotated by conventional means to facilitate adjustment of the form.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary perspective view of a portion of a form for casting structural concrete members which form includes an adjustable form lock embodying the present invention.

FIG. 2 is a transverse section of the form portion shown in FIG. 1 with a'side wall of the form being shown locked in the closed-form position.

FIG. 3 is a transverse section similar to FIG. 2 but with the side wall being shown in an open-form position leaving stripping draft between the side wall and cast member.

DESCRIPTION OF THE PREFERRED EMBODIMENT Looking now at FIG. 1, a portion of a form 10 for casting structural concrete members is shown. The form is preferably of metal construction and is mounted upon a foundation including a longitudinally extending angle 11 and a transverse channel 12. The form includes a bottom 13, which is securely mounted upon the transverse channel, and a side wall 14, which extends upwardly from the bottom with the junction thereof being filleted, as indicated at 15, and forming a resilient hinge.

Within the included angle between bottom 13 and side wall 14 is a form cavity 16 in which structural concrete members can be cast. While only a portion of this cavity is shown, it will be understood that the remainder of the cavity and corresponding form portion can vary with the desired shape of the structural member to be cast, examples of such being shown in my prior US. Pat. No. 3,071,834. The included angle between the bottom and the side wall of the form defines a corresponding corner of a structural concrete member 17, as shown in FIGS. 2 and 3. When the side wall is in an open-form stripping position, as shown in FIG. 3, additional angularity between the bottom and the side wall provides a spacing S between the top of the side wall and the cast concrete member for stripping draft. A flange 18 projects from the top of the side wall outwardly from the form cavity.

In order to pivot side wall 14 from the open-form stripping position shown in FIG. 3 to the closed-form casting position shown in FIG. 2, a suitable number of pivoting and locking devices 20 are provided at spaced longitudinal intervals and at a height providing adequate leverage upon the side wall. Each of such pivoting and locking devices includes a channel 21 having a web 22 welded to the side wall with a short flange 23 and long flange 24 projecting outwardly from the web to serve as vertical stiffeners. A shaft 25 extends logitudinally of the form through holes drilled in the channel flanges 23 and 24, and a crank 26 is provided for rotating the shaft. Positioned between the channel flanges and welded to the shaft is a cam block 27 which has an operating corner 28 radially spaced from the shaft axis of rotation and a locking surface 29 extending from the corner.

A channel 31 is welded upright on transverse channel 12 at a location spaced outward from side wall 14 to provide base support for a cantilever reaction member 32 that projects opposite operating corner 28 of cam block 27. With reference to FIG. 3, it will be seen that when crank 26 is in an elevated position, as indicated by center line 33, operating corner 28 does not contact the reaction member and side wall 14 is free to resiliently deflect outward providing stripping draft. An extension handle 34 can be fitted over the crank to obtain leverage in applying a force thereto for rotating the crank to a lowered position as indicated by centerline 35 (FIG. 3). As the shaft rotates, corner 28 engages reaction member 32 and forces side wall 14 inwardly to a closed-form casting position, as indicated in FIG. 2, and the flat locking surface 29 bears against the flat inner surface of the reaction member, thereby locking cam block 27 against accidental rotation due to internal form pressure acting against the side wall.

Backing up reaction member 32 opposite cam block 27 is an adjustable support member shown as a set screw 37 threadably fitted through rigid mounting means such as an elongated nut 38 that is mounted on a strap 39 welded to the upright channel 31. A slot 40 is provided in the end of the set screw facing outward from side wall 14 for receiving the blade of a screwdriver or the like by which means the set screw can be turned to a desired adjustment. It will be seen that side wall 14 can be adjusted to a true vertical closed-form casting position when locking surface 29 is in engagement with reaction member 32. By turning the set screw the reaction member will deflect inwardly accordingly, and the side wall moves in response thereto under the force exerted by shaft 25 acting against support channel 21. A lock nut 41, threadably fitted on the outwardly projecting end of the set screw, can be moved into engagement with the elongated nut 38 to prevent accidental turning of the set screw after a desired adjustment has been made.

Before casting a structural concrete member in form 10, side wall 14 is pivoted to a closed-form position by downward rotation of crank 26 until locking surface 29 engages reaction member 32. The inside dimension of the form is then measured to determine if the side wall is in a true closed-form position. Should it be necessary to adjust the side wall position, the adjustment can be made by turning set screw 37 until the side wall is properly aligned. Lock nut 41 is then turned to engage nut 38 and thereby prevent slippage of the set screw.

Form can then be filled with concrete in a fluid state, and flange l8 protects locking device from concrete spillage. The concrete is vibrated within the forms to insure a uniform distribution therein. After the concrete has been allowed to set for a desired period, crank 26 is rotated upwardly, to the position shown in FIG. 3, where cam block 27 is disengaged from reaction member 32 and side wall 14 is permitted to flex outwardly to an open-form stripping position. The structural concrete member 17 can then be removed from the form, and the operation can be repeated to cast another member.

Although the best mode contemplated for carrying out the present invention has been herein shown and described, it will be apparent that modification and variation may be made without departing from what is regarded to be the subject matter of the invention.

What is claimed is:

1. In a form for casting structural concrete members which form includes a bottom and a side wall attached to the bottom with the junction of said bottom and side wall forming a resilient hinge, said bottom and side wall normally defining an inclined angle therebetween equal to a corresponding corner angle of a member to be cast plus sufficient stripping draft for removing the cast member after the side wall has moved freely responsive to said resilient hinge but wherein said included angle can be reduced to equal the corresponding corner angle of the cast member by resiliently compressing the hinge and pivoting the side wall about the bottom until a closed-form position is reached, the improvement comprising means for pivoting the side wall about the bottom and locking the side wall in said closed-form position against the resilient strength of the hinge,

an adjustable support member for said pivoting and locking means,

means mounting said support member substantially in alignment with said pivoting and locking means when said side wall is in closed and locked position so as to counteract side wall reaction forces exerted by said resilient hinge, and,

means cooperatively associating said support mem ber and said mounting means to permit linear adjusting movement of said support member toward and away from said pivoting and locking means while supporting said side wall.

2. An improved form for casting structural concrete members as described in claim 1, wherein the side wall pivoting and locking means includes a reaction member and a crank operated cam adapted to bear against one side of the reaction member, and wherein said support member includes a set screw threadably adjustable to bear against the opposite side of the reaction member from the cam and thereby adjust the position of the reaction member relative to the cam.

3. An improved form for casting structural concrete members as described in claim 2, wherein said reaction member is a cantilever having a free end that can deflect in response to the positioning of said set screw.

4. An improved form for casting structural concrete members as described in claim 1, wherein said side wall pivoting and locking means includes a channel mounted on said side wall, a crank operated cam mounted within said channel for rotation about an axis in fixed parallel relationship to said side wall, and a cantilever reaction member supported independently of said side wall and projecting adjacent said cam to provide a side surface for said cam to bear against; and wherein said mounting means includes a fixed member mounted independently of said side wall, said support member comprises a set screw threadably fitted through said fixed member to bear against a side surface of said cantilever reaction member opposite from that engaged by said cam for positioning the cantilever reaction member relative to the cam, and a lock nut threadably fitted upon said set screw to bear against said fixed member and thereby maintain the set screw in position relative to the reaction member after adjustment thereof has been made.

5. An improved form for casting structural concrete members as described in claim 4 wherein said cam has a corner spaced radially from the axis of rotation to bear against said reaction member, and a flat surface extending from the corner to bear against said reaction member when said side wall is in said closed-form posi tion thereby locking the cam against accidental rota- 7. An improved form for casting structural concrete members as described in claim 6 including a flange projecting from said side wall above said pivoting and locking means and above said adjustable support member to protect against concrete spillage thereon, and an extension handle adapted to be coupled with said crank operated cam for additional leverage when applying a rotational force to said cam.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PATENT NO. I 3, 765,641

DATED October 16, 1973 INVENTOR(S) I LAWRENCE F. TUMEY It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

On front of patent add Assignee: FMC Corporation, San Jose,

California--.

Column 4, line 3, change "inclined" to --included--.

Signed and sealed this 3rd day of June 1975.

(SEAL) Attest:

C. MARSHALL DANN RUTH C. MASON Commissioner of Patents Attesting Officer and Trademarks 

1. In a form for casting structural concrete members which form includes a bottom and a side wall attached to the bottom with the junction of said bottom and side wall forming a resilient hinge, said bottom and side wall normally defining an included angle therebetween equal to a corresponding corner angle of a member to be cast plus sufficient stripping draft for removing the cast member after the side wall has moved freely responsive to said resilient hinge but wherein said included angle can be reduced to equal the corresponding corner angle of the cast member by resiliently compressing the hinge and pivoting the side wall about the bottom until a closed-form position is reached, the improvement comprising means for pivoting the side wall about the bottom and locking the side wall in said closed-form position against the resilient strength of the hinge, an adjustable support member for said pivoting and lOcking means, means mounting said support member substantially in alignment with said pivoting and locking means when said side wall is in closed and locked position so as to counteract side wall reaction forces exerted by said resilient hinge, and, means cooperatively associating said support member and said mounting means to permit linear adjusting movement of said support member toward and away from said pivoting and locking means while supporting said side wall.
 2. An improved form for casting structural concrete members as described in claim 1, wherein the side wall pivoting and locking means includes a reaction member and a crank operated cam adapted to bear against one side of the reaction member, and wherein said support member includes a set screw threadably adjustable to bear against the opposite side of the reaction member from the cam and thereby adjust the position of the reaction member relative to the cam.
 3. An improved form for casting structural concrete members as described in claim 2, wherein said reaction member is a cantilever having a free end that can deflect in response to the positioning of said set screw.
 4. An improved form for casting structural concrete members as described in claim 1, wherein said side wall pivoting and locking means includes a channel mounted on said side wall, a crank operated cam mounted within said channel for rotation about an axis in fixed parallel relationship to said side wall, and a cantilever reaction member supported independently of said side wall and projecting adjacent said cam to provide a side surface for said cam to bear against; and wherein said mounting means includes a fixed member mounted independently of said side wall, said support member comprises a set screw threadably fitted through said fixed member to bear against a side surface of said cantilever reaction member opposite from that engaged by said cam for positioning the cantilever reaction member relative to the cam, and a lock nut threadably fitted upon said set screw to bear against said fixed member and thereby maintain the set screw in position relative to the reaction member after adjustment thereof has been made.
 5. An improved form for casting structural concrete members as described in claim 4 wherein said cam has a corner spaced radially from the axis of rotation to bear against said reaction member, and a flat surface extending from the corner to bear against said reaction member when said side wall is in said closed-form position thereby locking the cam against accidental rotation due to internal form pressure acting against the side wall.
 6. An improved form for casting structural concrete members as described in claim 5 wherein said set screw is axially aligned substantially perpendicular to the side wall in said closed-form position and parallel to an extension of the bottom at a spacing therefrom of less than the side wall height, said set screw having an end that faces outward from the side wall adapted for turning.
 7. An improved form for casting structural concrete members as described in claim 6 including a flange projecting from said side wall above said pivoting and locking means and above said adjustable support member to protect against concrete spillage thereon, and an extension handle adapted to be coupled with said crank operated cam for additional leverage when applying a rotational force to said cam. 